XML 102 R75.htm IDEA: XBRL DOCUMENT v3.21.1

RELATED PARTY TRANSACTIONS - Summary of transactions with and amounts due from and due to related parties (Parenthetical) (Detail) ¥ in Thousands, $ in Thousands		1 Months Ended	12 Months Ended
	Apr. 22, 2020 CNY (¥)	Sep. 30, 2020 CNY (¥)	Dec. 31, 2020 CNY (¥) Instalment	Dec. 31, 2020 USD ($) Instalment	Dec. 31, 2019 CNY (¥)	Dec. 31, 2018 CNY (¥)	Dec. 31, 2019 USD ($)
Related Party Transaction [Line Items]
Lump-sum cash payment			¥ 37,372	$ 5,728		¥ 11,550
Business combination under common control			3,000
Additional Paid-In Capital [Member]
Related Party Transaction [Line Items]
Business combination under common control			3,000
Loans To Related Parties
Related Party Transaction [Line Items]
Loans to related parties			542		¥ 123,947	¥ 11,550
Subsidiary Director | Loans To Related Parties
Related Party Transaction [Line Items]
Loans to related parties			¥ 79
Interest rate on loan receivable			6.00%	6.00%
Number of loan instalments | Instalment			36	36
China Smartpay
Related Party Transaction [Line Items]
Interest rate on loan receivable					9.00%		9.00%
Loans					¥ 119,924		$ 17,225
Interest receivable		¥ 7,570			¥ 4,938
Lump-sum cash payment		¥ 37,372
SG Fintech Joint Stock Company
Related Party Transaction [Line Items]
Interest rate on loan receivable					0.50%		0.50%
Loans					¥ 598		$ 86
Interest receivable					1
SG Fintech Joint Stock Company | Shanghai Zhundian Enterprise Service Co., Ltd [Member]
Related Party Transaction [Line Items]
Net assets	¥ 3,000
SG Fintech Joint Stock Company | Shanghai Zhundian Enterprise Service Co., Ltd [Member] | Additional Paid-In Capital [Member]
Related Party Transaction [Line Items]
Business combination under common control	¥ 3,000
SG Fintech Joint Stock Company | Loans To Related Parties
Related Party Transaction [Line Items]
Loans to related parties					¥ 598

X

- Definition

Interest Rate On Loan Receivable

+ References

No definition available.

+ Details

Name:	jfin_InterestRateOnLoanReceivable
Namespace Prefix:	jfin_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Number of loan instalments.

+ References

No definition available.

+ Details

Name:	jfin_NumberOfLoanInstalments
Namespace Prefix:	jfin_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of net assets (liabilities).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77885760&loc=SL35686385-199418

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 205
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=118262037&loc=d3e9915-115836

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 220
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-09(7))
-URI http://asc.fasb.org/extlink&oid=120401555&loc=SL114874367-224272

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section S99
-Paragraph 2
-Subparagraph (SX 210.6-05(4))
-URI http://asc.fasb.org/extlink&oid=120401414&loc=d3e604008-122996

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 220
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-09(6))
-URI http://asc.fasb.org/extlink&oid=120401555&loc=SL114874367-224272

+ Details

Name:	us-gaap_AssetsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_InterestReceivable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

The amount for notes payable (written promise to pay), due to related parties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.17)
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

Name:	us-gaap_NotesPayableRelatedPartiesCurrentAndNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

The cash outflow associated with extending a long-term loan to a related party. Alternate caption: Payments for Advances to Affiliates.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3213-108585

+ Details

Name:	us-gaap_PaymentsToFundLongtermLoansToRelatedParties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

The cash inflow associated with collection, whether partial or full, of long-term loans to a related party. Alternate caption: Proceeds from Advances to Affiliates.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3179-108585

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

+ Details

Name:	us-gaap_ProceedsFromCollectionOfLongtermLoansToRelatedParties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_RelatedPartyTransactionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Value of stock issued pursuant to acquisitions during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29-31)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_StockIssuedDuringPeriodValueAcquisitions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AdditionalPaidInCapitalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=jfin_LoansToRelatedPartiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=jfin_SubsidiaryDirectorMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=jfin_ChinaSmartpayMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=jfin_SgFintechJointStockCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_BusinessAcquisitionAxis=jfin_ShanghaiZhundianEnterpriseServiceCoLtdMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: